1. Field of the Invention
The present invention relates to the automatic welding of metal plates.
More precisely, such metal plates include plane areas framed by corrugations running in two perpendicular directions and intersecting to form abutment surfaces at the ends of the corrugations.
These plates, which are obtained by bending and shaping initially plane plates by means of suitable stamps so as to obtain first the corrugations in one direction and then the corrugations in the other direction, are commonly called "waffle plates." At the meeting point of the corrugations, distortions of the corrugations are naturally formed, with folds or bends which constitute abutment surfaces at the ends of the corrugations.
By abutment surface it is intended to signify that by following the corrugations bordering the plane areas one abuts against the said surfaces at each end of the corrugations.
The automatic welding of such plates appears very attractive, especially in the case of the assembly of a large number of plates, for example for the constructions of tanks or reservoirs, and in particular on ships for transporting liquefied gas and for the storage of liquefied gases on land.
2. Description of the Prior Art
Welding apparatus are known which comprise a support designed to support the carriage of a welding head, but the known supports are not usable for the welding of waffle plates.